08/02/2010 01:41 pm ET | Updated May 25, 2011

California Water Demand Could Exceed Supply By 2050

This story comes courtesy of California Watch

By Agustin Armendariz

Even without climate change, much of California is at high risk of water demand exceeding supply by 2050, according to a report released this month.

The National Resources Defense Council commissioned environmental consulting firm Tetra Tech to perform an assessment of water supply and demand under future climate and growth scenarios. Much of the United States could face water shortages, but water sustainability is at extreme risk in the Great Plains and the southwest United States, according to the analysis.

Without climate change, Contra Costa, Sacramento, San Bernardino and Riverside counties face an extreme risk of water shortages. Factoring in climate change, many of the populous areas of the state enter the extreme risk category.

The report emphasizes that it "was not intended to predict where water shortages will occur, but rather where they are more likely to occur."

At the end of last year, state lawmakers passed legislation putting Proposition 18 in the November ballot, which would take measures to address diminishing water supplies and attempt to restore the environmentally degraded Sacramento-San Joaquin River Delta, among other things. The delta provides two-thirds of the state's drinking water, according to the article.

"The bond and its accompanying policy directives were hailed as the most significant advancement in California water planning in 50 years," according to the San Diego Union-Tribune.

Now the water bond has become "a victim of the budget crisis," with supporters, including Gov. Arnold Schwarzenegger calling for its removal from the November ballot, according to the article.

"Estimated water withdrawal as a percentage of available precipitation is generally less than 5 percent for the majority of the eastern United States, and less than 30 percent for the majority of the western United States. But in some arid regions (such as Texas, the Southwest and California) and agricultural areas, water withdrawal is greater than 100 percent of the available precipitation."

The full report is available on the NRDC web site.